This application claims the priority benefit of Taiwan application serial no. 90114375, filed Jun. 14, 2001.
1. Field of the Invention
The invention relates in general to a package method for an organic electro-luminescent (OEL) display, which applies a certain amount of ultra-violet (UV) or thermal curing resin on a lamination plate or a substrate and obtains a global application by forming a trench at an edge of the lamination plate.
2. Description of the Related Art
In the conventional package method of OEL display, a frame sealant is formed using a syringe to spread a UV curing resin around a device under an inert gas (nitrogen or argon) environment. In this way, the substrate and the lamination plate are adhered together to protect the device from being corroded by moisture. The frame sealant, however, made of polymer, cannot perfectly prevent permeation of moisture, so that the commercial requirement in lifetime cannot be achieved. Studies in thin film structure, material and package process of packages for electro-luminescent display devices have been commenced by a lot of companies and researchers. The research of package process has focused on disposing drying agent or moisture absorber into the device or electroplating one or several layers of protection films on the device structure.
In terms of disposing moisture absorber inside of the device, Idemitsu Kosan filed a package method patent in 1995 (U.S. Pat. No. 5,962,962). In this package method, inert liquid layer mixed with drying agent is formed inside the device. In another package method disclosed in U.S. Pat. No. 5,882,761 by Pioneer, a metal lamination plate with a recess is used, and a drying substance is applied into the recess. Thereby, the moisture permeating into the device is absorbed, and the device lifetime is lengthened. The purpose for depositing one or several protection films on the device structure is to completely block the moisture in the external environment to permeate into the device. In this regard, protection films made of organic and inorganic materials have been discussed. For example, Motorola disclosed a patent of protection film in 1995 (U.S. Pat. No. 5,811,177), in which inert metal, inorganic protection film and resin sealant are coated on the device structure.
Referring to FIG. 1 and FIG. 2, the R.O.C Patent No. 87117618 issued to Highlight Optoelectronics Inc. disclosed a package method, which applies a screen printing process to coat a UV curing resin 106 on a lamination plate 104. A substrate 100 comprising an OEL display 102 thereon is then aligned with the lamination plate 104. By pressure and thermal processes, the package of the OEL display 102 is complete.
The above screen printing process for coating the UV curing resin on the lamination requires frequent change and cleaning of printing boards. Therefore, a mass production under an inert gas environment cannot be achieved by such method.
In addition, microscopically, the UV curing resin coated on the lamination plate by screen printing process has an uneven surface. During lamination process of the lamination plate and the substrate, bubbles are likely produced near the surface of the OEL display. Further, the dimension of the UV curing resin is difficult to control during the lamination process.
The present invention provides a package method for an organic electro-luminescent (OEL) display. By applying a certain amount of UV curing resin or thermal curing resin on either a lamination plate or a substrate, and by forming a trench at an edge of a lamination plate, a global coating effect can be obtained. Consequently, the adhesion between the UV or thermal curing resin, the lamination plate, and the substrate is significantly improved. Further, the dimension of the UV or thermal curing resin can be precisely controlled.
By obtaining the global coating effect, the package method for an OEL display mentioned allows mass production under an inert gas environment.
Accordingly, the present method provides a package method and a package apparatus for an OEL display. A panel on which an OEL display is formed is provided by a panel supply system. A lamination plate is provided by a lamination plate supply system. A UV or thermal curing resin is coated on either the lamination plate or the panel. The lamination plate and the panel are aligned and laminated with each other. By applying a UV radiation or a thermal process, the UV or thermal resin is cured to form a frame sealant between the panel and the lamination plate. In the alignment and lamination process, the space dimension between the panel and the lamination plate is controlled by adjusting lamination pressure and movement of the lamination machine. The exceeding UV or thermal resin flows into the trench at the edge of the lamination plate, so that the dimension thereof is well controlled. The coating pattern of the UV or thermal curing resin includes dots, circles, rectangles, parallel straight lines, cross lines, or a tree pattern. The shape of the trench includes a continuous grooves or multiple broken straight grooves distributed at the edge of the lamination plate, such that the function for controlling dimension of the UV or thermal curing resin can be achieved.
Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.